A self-assembled monolayer (SAM) of 4-aminothiophenol (4-ATP) was formed on copper surface which was characterized using cyclic voltammetry, Fourier transform infrared spectroscopy, and Raman spectroscopic techniques. The surface morphology of the monolayer was examined by scanning electron microscopy. The anticorrosive property of the SAM was investigated using electrochemical impedance spectroscopy and polarization studies. The electrochemical measurements showed that the inhibition efficiency increased with the immersion time of copper in ethanolic solution of 4-ATP in 3.5% NaCl. The significant corrosion protection efficiency of SAM could be due to the compact and dense monolayer on metallic surfaces.